Telescopically assembled electrical cartridge which is yieldably clamped to a panel

ABSTRACT

A tubelike cartridge is disclosed for mounting an electrical assembly on a panel having an opening therein. The cartridge comprises a pair of telescoping inner and outer sleeves, and a clamping mechanism which is yieldably biased to clamp the edge of the panel opening between the sleeves against the bias thereon.

United States Patent Inventors James W. Amls, Jr.

Bellevue;

Maurlce I). Fuller, Mercer Island; James B. Dohimn, Seattle, all ol Wash.

May 22, I969 Oct. 5, I971 Kerry Manufacturing Company Seattle, Wash. 1

Appl. No. Filed Patented Assignce TELESCOPICALLY ASSEMBLED ELECTRICAL CARTRIDGE WHICH IS YIELDABLY CLAMPED TO A PANEL 15 Claims, 3 Drawing Figs.

U.S. Cl 339/ 132 R, 248/27 Int. Cl Ilolr 13/60 Field of Search 339/132,

[56] References Cited UNITED STATES PATENTS l,079,483 l l/l9l 3 Freeman 339/l 29 3,090,949 5/1963 Ha|lcrherg..... 339/129 X 3,504,875 4/l970 Johnson et al. 248/27 FOREIGN PATENTS 658,761 l/l929 France 339/l 29 Primary Examiner-Richard E. Moore Attorney-Christensen & Sanborn ABSTRACT: A tubelike cartridge is disclosed for mounting an electrical assembly on a panel having an opening therein. The cartridge comprises a. pair of telescoping inner and outer sleeves, and a clamping mechanism which is yieldably biased to clamp the edge of the panel opening between the sleeves against the bias thereon.

'IELESCOPICALLY ASSEMBLED ELECTRICAL CARTRIDGE WHICH IS YIELDABLY CLAMPED TO A PANEL Field of the Invention BACKGROUND OF THE INVENTION INCLUDING CERTAIN OBJECTS THEREOF Electrical assemblies such as pushbutton switches are often mounted in small tubelike cartridges on a panel. The cartridges are installed in'individual openings in the panel, and if possible, the process of securing them to the panel is conducted on the front side thereof, that is, on the side from which the assemblies are operated.

One object of the present invention is to provide a small tubelike cartridge of this nature which can be installed in a panel opening and clamped to the edge of the opening by a process conducted on the front side of the panel. Another object is to provide a cartridge of this nature which is self-adjusting when it is clamped to the panel, so as to allow for differences in thickness from one panel to another, caused for example, by differences in mill tolerances or the presence of a paint coating on the panel. A further object is to provide a cartridge of this nature which cannot be overtightened when it is clamped to the panel so as to risk damaging the clamping components which, of necessity, are small and delicate in miniature devices of this nature. Other objects include the provision of a cartridge of this nature which is highly durable in construction and has a relatively small number of readily interchangeable parts that are cheaply manufactured and easily assembled with one another. Still further objects will become apparent from the description of the invention which follows hereafter.

SUMMARY oF THE INVENTION These objects and advantages are realized by a small tubelike cartridge of our invention which comprises a pair of telescoping inner and outer sleeves, and a clamping mechanism which is yieldably biased to clamp the edge of the panel opening between the sleeves against the bias thereon. The clamping mechanism comprises a pair of relatively shiftable stops which are yieldably biased in the opposite endwise directions of the sleeves, and an adjustable clamping means which is operative to clamp the edge of the opening between the sleeves against the bias on the stops. Preferably, the stops are coaxially aligned with the sleeves and are yieldably biased at a plurality of peripherally distributed points thereon which are symmetrically disposed about the cross-sectional area of the sleeves so as to balance the clamping forces on the edge of the opening. Moreover, one of the stops is rigidly carried on the inner sleeve and the other is slidable therein; and the clamping means is operatively interconnected with the slidable stop and the outer sleeve to apply the clamping forces in the opposite endwise directions thereof, there being an outtumed flange on the projecting forward end portion of the inner sleeve which is coopetable with the outer sleeve to clamp the edge of the panel opening therebetween. There may also be another pair of relatively shiftable stops on the opposite sides of the slidable stop to limit the travel thereof.

In the preferred embodiments of the invention, the slidable stop comprises a floating compression block which is adapted for mounting electrical components of the assembly in the sleeves. The block is slidably engaged in the inner sleeve and yieldably biased in the open end direction of the cartridge by a plurality of peripherally distributed resilient compression elements caged between the block and an equal number of rigid stops on the sleeve. ln addition, there is a base carried on the rear end portion of the outer sleeve, and the clamping means includes a clamping screw which is rotatably mounted at a central location in the block, and interengaged with a threaded bore in the base. Preferably, the base is detachably connected with the rear end portion of the outer sleeve, and in the clamping process, the rotation of the screw operates to clamp the base against the end of the sleeve, when the edge of the opening is clamped between the flange on the inner sleeve and the adjacent forward end of the outer sleeve. The travel of the block is limited by a pair of stops on the screw and the inner sleeve, between the block and the base, and the block and the open end of the cartridge, respectively.

In certain embodiments, the clamping screw has an Allen head socket therein, and the socket has a circumferential lip formed about the mouth thereof to cooperate with the latch mechanism of a pushbutton cap such as is disclosed in our copending application Ser. No. 826,962 filed on even date herewith.

BRIEF DESCRIPTION OF THE DRAWINGS These and other features of the invention will be better'understood by reference to the accompanying drawing wherein one of the preferred embodiments of the invention is employed to mount an illuminated electrical pushbutton switch assembly on a panel.

In the drawings:

FIG. I is a part cross-sectional view of the cartridge in mounted position on a panel;

FIG. 2 is a part cross-sectional view of the cartridge in mounted position on a panel of greater thickness; and

FIG. 3 is an exploded perspective view of the cartridge illustrating the various components therein.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing, it will be seen that the cartridge 2 comprises a pair of rectangular metal sleevelike tube sections 4 and 6 which are telescopically engaged in one another. The inner sleeve 4 has an out-tumed flange 7 on the open forward end portion 4' thereof, and several cutouts 8 and I0 and crimpings 12 in the rear end portion 4 thereof. One of the cutouts takes the form of a short axially extending slotlike indentation 8- in the rear end of the sleeve; while the other two are in the form of U-shaped corner cutouts I0 which form bendable tabs 14 in the sidewalls of the sleeve. The crimpings are also developed at the rear end of the sleeve, where the corners are inwardly crimped to form a set of stops I2 the function of which shall be explained shortly. The outer sleeve 6 has a rectangular opening 16 in one of the larger dimension sidewalls thereof; and a pair of wide groovelike recesses I8 in the rear end edges of its narrower sidewalls.

The cartridge also comprises a floating insulative ceramic compression block 20 which is slidably guided in the inner sleeve 4 and yieldably biased in the direction of the open end 4' of the cartridge. The block has three spaced, mutually parallel and transversely aligned bores 22 therethrough, the outer two 22 of which have a pair of spring loaded electrical contacts posts 24 mounted therein. The center bore 22" is disposed on the axis of the block and is adapted to receive a specially devised Allen head screw 26 which has an elongated, stepped cylindrical head 26' thereon, that in turn, has a stepped deeply recessed socket 28 therein. The screw is inserted in the block until the wider diameter shoulder 30 thereon abuts the upper end face 20' of the block; whereupon the threaded tip 32 of the screw projects well below the lower end face 20" of the block for interengagement with the base 34 of the cartridge as shall be explained. One of the posts 24 also has a projecting tip 24' thereon which makes contact with an apertured printed circuit board 36 in the base, there being a bus bar connection (not shown) between the posts which enables them to be conjointly energized from the board.

The compression block is also structurally developed in two other regards. An axially extending groove 38 is formed in one sidewall of the block from the rear end thereof; and each of the corner portions 39 of the block is relieved well along the axial length of he block from the rear end thereof, so that the comer shoulders 40 of the end are deeply inset therefrom. As a consequence, when the block is slidably inserted in the inner sleeve, a set of peripheral cages 42 are formed in the corners of the sleeve which can house an equal number of coiled springs 44 that are inserted therein on capped guide pins 46. The caps of the pins rest on the erimped stops 12 formed at the lower end of the sleeve, and thus interengage the springs between the stops and the shoulders 40 of the block.

The base 34 of the cartridge has a large rectangular recess 48 in the body thereof, and the periphery of the recess is rabbetted to form a supporting shoulder 50 for the circuit board 36 at approximately midway into the recess. The larger dimension sidewalls of the base and the adjoining corners of the narrower walls are also relieved to form a pair of broadly dimensioned tongues 52 which project from the end edges of the base. The tongues are sized to interengage with the groovelike recesses 18 in the end edges of the outer sleeve; and in addi-- tion, an axially extending rib S4 is formed within the recess 48 of the base, on one of the tongued walls of the same. The rib is sized to interengage with the groove 38 and the slot 8 in the compression block and the inner sleeve.

At the center of the recess, on the axis of the base, there is a raised cylindrical column 56, and the column in turn has a cylindrical bore 58 therein which passes through the base. The bore is adapted to receive a flanged clamping nut 60 which is inserted into the bore 58 from the rear of the base until the flange 60' abuts against the end face 34' thereof. Thereafter, a rectangular terminal plate 62 is secured over the face, as by means of a set of fixed terminal posts which are omitted from the drawing as not being material to the invention described herein. The terminal posts are connected with the circuit board 36 and the assembly is retained on the shoulder of the recess by passing the nut through an aperture 64 in the board and flaring the unthreaded forward end 60" of the nut 60 until it flanges over the board and clamps it against the top of the column 56.

As seen, the bottommost portion 28' of the socket 28 in the screw 26 has a characteristic Allen head cross section therein, for purposes of engaging the longer arm of an Allen head wrench therewith. When the cartridge is assembled, the compression block is inserted in the inner sleeve 4 so as to trap the springs 44 in their respective cages 42, and the tabs 14 of the inner sleeve are bent over the forward end 20' of the block to slidably interengage it with the sleeve. Moreover, after the screw has been inserted in the center bore 22" of the block, a retainer nut 66 and lock washer 68 are engaged on the tip 32 of the screw to assure that it remains with the block. Subsequently, when the cartridge is mounted on the panel 70, the inner sleeve is passed through the opening 72 therein from the front side 70' of the panel, and the outer sleeve 6 is then slipped over the inner sleeve 4 from the other side 70" of the panel and abutted thereagainst. Next, after any electrical connections have been made to the base 34, it is interengaged in tongue and groove fashion with the grooved end 18 of the outer sleeve, and the tip 32 of the screw is interengaged with the clamping nut 60. As the screw is tightened into the clamping nut, the retainer nut 66 and the lock washer 68 are clamped between the narrower diameter shoulder 74 of the screw and the flange 60" of the retainer nut, and the screw is thus "bottomed" against the base. Ordinarily, this effect also indicates that the edge of the panel opening 72 is clamped between the flange 67 of the inner sleeve and the adjacent end 6 of the outer sleeve (there also being an elastomeric moisture seal 76 interposed between the flange and the edge of the panel, as is explained in out copending application Ser. No. 826,963 filed on even date herewith). However, should the panel be thicker than expecteddue perhaps to a difference in mill tolerance, or to the presence of a paint film thercon--the difference in thickness is taken up in the compression of the springs 44 as seen by a comparison of H65. 1 and 2. Thus, in H0. 2, the greater thickness of the panel requires that the block disengage from the tabs 44 and move deeper into the cartridge from the flange, against the bias on the springs.

We claim:

1. A tubelike cartridge for mounting an electrical assembly on a panel having an opening therein, comprising a pair of telescoping inner and outer sleeves, and a clamping mechanism comprising a pair of relatively shiftable stops which are rigidly carried on and slidable in the inner sleeve, respectively, and yieldable biased in the opposite endwise directions of the sleeves, and an adjustable clamping means which is operative to clamp the edge of the panel opening between the sleeves against the bias on the stops.

2. The cartridge according to claim 1, wherein the stops are coaxially aligned with the sleeves and are yieldably biased at a plurality of peripherally distributed points thereon which are symmetrically disposed about the cross sectional area of the sleeves so as to balance the clamping forces on the edge of the opening.

3. The cartridge according to claim 1 wherein the clamping means is operatively interconnected with the slidable stop and the outer sleeve to apply the clamping forces in the opposite endwise directions thereof, there being an out-turned flange on the projecting forward end portion of the inner sleeve which is cooperable with the outer sleeve to clamp the edge of the opening therebetween.

4. The cartridge according to claim 1 wherein there is also another pair of relatively shiftable stops on the opposite sides of the slidable stop to limit the travel thereof.

5. The cartridge according to claim 1 wherein the slidable stop comprises a floating compression block which is adapted for mounting electrical components of the assembly in the sleeves.

6. The cartridge according to claim 5 wherein the block is slidably engaged in the inner sleeve and yieldably biased in the open end direction of the cartridge by a plurality of peripherally distributed resilient compression elements caged between the block and an equal number of rigid stops on the sleeve.

7. The cartridge according to claim 6 having a base carried on the rear end portion of the outer sleeve, and wherein the clamping means includes a clamping screw which is rotatably mounted at a central location in the block, and interengaged with a threaded bore in the base.

8. The cartridge according to claim 7 wherein the base is detachably connected with the rear end of the outer sleeve and operatively clamped against the end of the sleeve when the edge of the panel opening is clamped between the flange on the inner sleeve and the adjacent forward end of the outer sleeve.

9. The cartridge according to claim 7 wherein the travel of the block is limited by a pair of stops on the screw and the inner sleeve, between the block and the base, and the block and the open end of the cartridge, respectively.

10. The cartridge according to claim 7 wherein the clamping screw has an Allen head socket therein.

11. The cartridge according to claim 10 wherein the socket has a circumferential lip formed about the mouth thereof.

12. In a cartridge for mounting an electrical assembly on a panel having an opening therein, three telescoping relatively innermost, outermost, and intermediate members, means interconnecting the innermost and intermediate members and operative to relatively yieldably bias said latter members in the opposite endwise directions of the members, and means interconnecting the innermost and outermost members and operative to clamp the edge of the opening between the intermediate and outermost members against the bias on the inncrmost and intermediate members.

13. lo a cartridge for mounting an electrical assembly on a panel having an opening therein, a base adapted to be arranged opposite the edge of the opening on one side of the panel, a sleeve adapted to be slidably inserted in the opening, a stop relatively shiftably mounted in the sleeve, yicldable biasing means interposed between the stop and the sleeve, to

bias the same in the opposite endwise directions of the sleeve, means interconnecting the'stop with the base'and operative to clamp theedge of the opening between the base and the sleeve against the bias on the stop and the sleeve.

14. In a cartridge for mounting an electrical assembly on a panel having an opening therein, a pair of telescoping inner and outer sleeves, a pair of relatively shiftably mounted stops in the inner sleeve which are yieldably biased in the opposite endwise directions thereof, and a clamping mechanism interconnecting one of the stops with the outer sleeve and operative to clamp the edge of the opening between the sleeves against the bias on the stops.

15. In a cartridge for mounting an electrical assembly on a .panel having an opening therein, a base adapted to bear- 

1. A tubelike cartridge for mounting an electrical assembly on a panel having an opening therein, comprising a pair of telescoping inner and outer sleeves, and a clamping mechanism comprising a pair of relatively shiftable stops which are rigidly carried on and slidable in the inner sleeve, respectively, and yieldable biased in the opposite endwise directions of the sleeves, and an adjustable clamping means which is operative to clamp the edge of the panel opening between the sleeves against the bias on the stops.
 2. The cartridge according to claim 1, wherein the stops are coaxially aligned with the sleeves and are yieldably biased at a plurality of peripherally distributed points thereon which are symmetrically disposed about the cross sectional area of the sleeves so as to balance the clamping forces on the edge of the opening.
 3. The cartridge according to claim 1 wherein the clamping means is operatively interconnected with the slidable stop and the outer sleeve to apply the clamping forces in the opposite endwise directions thereof, there being an out-turned flange on the projecting forward end portion of the inner sleeve which is cooperable with the outer sleeve to clamp the edge of the opening therebetween.
 4. The cartridge according to claim 1 wherein there is also another pair of relatively shiftable stops on the opposite sides of the slidable stop to limit the travel thereof.
 5. The cartridge according to claim 1 wherein the slidable stop comprises a floating compression block which is adapted for mounting electrical components of the assembly in the sleeves.
 6. The cartridge according to claim 5 wherein the block is slidably engaged in the inner sleeve and yieldably biased in the open end direction of the cartridge by a plurality of peripherally distributed resilient compression elements caged between the block and an equal number of rigid stops on the sleeve.
 7. The cartridge according to claim 6 having a base carried on the rear end portion of the outer sleeve, and wherein the clamping means includes a clamping screw which is rotatably mounted at a central location in the block, and interengaged with a threaded bore in the base.
 8. The cartridge according to claim 7 wherein the base is detachably connected with the rear end of the outer sleeve and operatively clamped against the end of the sleeve when the edge of the panel opening is clamped between the flange on the inner sleeve and the adjacent forward end of the outer sleeve.
 9. The cartridge according to claim 7 wherein the travel of the blocK is limited by a pair of stops on the screw and the inner sleeve, between the block and the base, and the block and the open end of the cartridge, respectively.
 10. The cartridge according to claim 7 wherein the clamping screw has an Allen head socket therein.
 11. The cartridge according to claim 10 wherein the socket has a circumferential lip formed about the mouth thereof.
 12. In a cartridge for mounting an electrical assembly on a panel having an opening therein, three telescoping relatively innermost, outermost, and intermediate members, means interconnecting the innermost and intermediate members and operative to relatively yieldably bias said latter members in the opposite endwise directions of the members, and means interconnecting the innermost and outermost members and operative to clamp the edge of the opening between the intermediate and outermost members against the bias on the innermost and intermediate members.
 13. In a cartridge for mounting an electrical assembly on a panel having an opening therein, a base adapted to be arranged opposite the edge of the opening on one side of the panel, a sleeve adapted to be slidably inserted in the opening, a stop relatively shiftably mounted in the sleeve, yieldable biasing means interposed between the stop and the sleeve, to bias the same in the opposite endwise directions of the sleeve, means interconnecting the stop with the base and operative to clamp the edge of the opening between the base and the sleeve against the bias on the stop and the sleeve.
 14. In a cartridge for mounting an electrical assembly on a panel having an opening therein, a pair of telescoping inner and outer sleeves, a pair of relatively shiftably mounted stops in the inner sleeve which are yieldably biased in the opposite endwise directions thereof, and a clamping mechanism interconnecting one of the stops with the outer sleeve and operative to clamp the edge of the opening between the sleeves against the bias on the stops.
 15. In a cartridge for mounting an electrical assembly on a panel having an opening therein, a base adapted to be arranged opposite the opening, a sleeve adapted to be inserted in the opening, and a mechanism for clamping the cartridge to the panel, including a stop which is slidably mounted in the sleeve, yieldable biasing means caged between the stop and the sleeve to bias the same in the opposite endwise directions of the sleeve, and means interconnecting the stop with the base to clamp the edge of the panel opening between the sleeve and the base against the bias on the stop and the sleeve. 